1. Field of the Invention
The present invention relates to a capacitive touch panel and a fabricating method thereof, and particularly relates to a capacitive touch panel and a fabricating method thereof for improving visual effects.
2. Description of Related Art
As technology advances, digital appliances, such as mobile phones, personal digital assistants, notebooks, and plane computers, are developed to be more convenient, multi-function, and exquisite. Screens are indispensable interface between users and these mobile phones, personal digital assistants, notebooks, and plane computers. Through screens, users may operate these products more conveniently. At present, liquid crystal display devices are utilized as screens in most products.
As information technology, wireless mobile communication, and information electric appliances rapidly develop in recent years, input devices for a great many information electronic products have been changed from conventional keyboards and mice to touch panels for the purposes of convenience, miniaturization, and being user-friendly. Especially, a capacitive touch liquid crystal display device has become the most popular product among all.
FIGS. 1A and 1B respectively illustrate a top view and a cross-sectional view of a conventional capacitive touch panel. As shown in FIGS. 1A and 1B, a conventional capacitive touch panel 100 comprises a substrate 110, a plurality of first touch pads 120, an insulator layer 130, and a plurality of second touch pads 140. To be more specific, the first touch pads 120 are disposed on the substrate 110 and electrically connected with one another by first connection lines 128, and the first touch pads 120 are arranged along a first direction D1. The insulator layer 130 is disposed on the substrate 110 to cover the first touch pads 120. The second touch pads 140 are disposed on the insulator layer 130 and electrically connected with one another by second connection lines 148, and the second touch pads 140 are arranged along a second direction D2, wherein the first touch pads 120 and the second touch pads 140 do not exist any opening and a region between each first touch pad 120 and each second touch pad 140 does not exist any pattern. The first touch pads 120 and the second touch pads 140 constitute a sensing array on the substrate 110 to achieve the purpose of plane sensing.
Based on the above, when the user touches the capacitive touch panel 100 by finger and the position where the first touch pads 120 and the second touch pads 140 are disposed contacted by the finger causes a capacitance change due to the equivalent series connection between the finger and the parasitic capacitance of the original touch pads. The change of capacitance is converted into a current signal which is transmitted to a control circuit board. After a central processing unit processes the data and calculates to obtain a result, the control circuit board thereby outputs a display signal to the display panel, and the display panel displays images to the user.
However, the touch pads in this type of capacitive touch panel are fabricated in different layers, which easily causes the discrepancy of transmittance between different layers, as Light T1 and Light T3 in FIG. 1B. Further, because the touch pads are disposed in different layers, the transmittance uniformity of the whole capacitive touch panel is also influenced by the positions of the touch pads. For instance, referring to FIG. 1B, the transmittance obtained when Light T2 passes through the capacitive touch panel is different from that obtained when Light T1 and T3 pass through the capacitive touch panel. The above factors all cause the problem of color aberration when the user watches the capacitive touch panel.
Additionally, when the capacitive touch panel is applied into a display panel or an opto-electronic device, the user may notice the touch pads of the capacitive touch panel. The discrepancy of display quality becomes even more obvious between the areas with and without the touch pads. Hence, how to improve the whole display uniformity and visual effects of the capacitive touch panel has become a challenge in the technology of fabricating capacitive touch panels.